Process of dyeing



UNITED s'rAres PATENT OFFICIE.

HARRY B. SMITH, 0F ALBANY, NEW YORK, ASSIGNOR T0 SUBPASS CHEMICAL 00.,

- INC., A CORPORATION OF NEW YORK. l a I PROCESS OF DYEING.

No Drawing.

To all whom it may concern Be it known that I, HARRY B. SMITH, a citizen of the United States, and a resident of Albany, in the county of Albany and State of New York, have invented a new and usefulProcess of Dyeing, of which the following is a specification.

My invention relates to a process of dye ing cotton material.

This invention is a form of the broad invention described and claimed in the patent to I. J. Smith and myself No. 1,199,745 issued September 26, 1916.

Like the process of that patent the present process is primarily adapted for use on unbleached knitted cotton goods containing motes, shives and, or,'leaf. The process is applicable to any class of cotton goods or yarns from Which it is desired to remove motes, shives and, or, leaf and dye the material. These motes, shives and, or, leaf are removed for the purposes of this invention, whether they are removed mechanically or are put in such condition that they will properly take the dye, and so are not detected by the eye. In this process, as in'that of the patent above mentioned, the dyeing and the treatment of the goods with an alkaline oxidizingagent is carried out in the.

same bath. The goods under treatment are also slightly bleached by the use of this process but the bleaching to whatever extent it exists is only incidental.

It hasbeen found that with some shades of dyestuff, such as, for instance, blues, drabs and pinks, if the goodsare first subjected to the alkaline oxidizing agent and the dyestuff subsequently added to the same bath, the dye does not dye the goods, the dye apparently being rendered ineffective bythe agent before the goods are dyed. If, however, the goods are first subjected to a dyestuff so that they are dyed and the alkaline oxidizing agent is subsequently added to the same bath, the dyestufi' on the fiber of the goods is apparently not affected by the agent although the agent has the desired eifecton the goods of removing the specks of motes, shives and, or, leaf and bleaching the goods to a certain degree. This is true with all shades of dye whether the dye is such that it is rendered ineffective when in the bath by the agent or not.

It will, therefore, be seen that this form Specification of Letters Patent.

Patented Feb. 1 5, 1921.

Application filed January 30, 1920. Serial No. 355,171.

of the patented invention is included in the b road principles of said invention and consists speclfically 1n subjecting the goods first to the dye and later to the agent in the same bath instead of subjecting the goods first to the agent and then to the dye in the same bath as is done in the specific example as set forth 1n the specification of the patent above mentloned. The specific form of the invent1on as described herein has some advantages over the specific procedure set out in the patent in that any dye can be used whether or not it is affected when in the bath by the alkaline oxidizing agent.

I The alkaline oxidizing agent for the bath 1s preferably composed of about one-half each of peroxid of sodium and an alkaline sodlum salt and is used in the proportion of about 3% of the weight of the goods under treatment. Such a solution as this is strongly alkallne and at the same time oxidizing and because it is strongly alkaline the time required for removing the motes,shives and, or, leaf is much reduced as compared w th any process prior to that set forth in sand patent. The alkalinity is not sufficiently intense to harden the material to be dyed. The above solution has been found to operate wlth entire satisfaction but it is understood that any oxygen-liberating prodnot, but preferably those corresponding to the per salts, along with an alkaline salt such as soda ash, sodium silicate, caustic soda, sodium phosphate, alone, or a mixture of any of these salts or certain other alkalines will give satisfactory results. For instance, peroxid of hydrogen, per carbonate of sodium, perborate of sodium, persulfate of sodium or persilicate of sodium may be used with a suitable alkaline salt or a mix ture of salts such as those above mentioned, although the best results are obtained with peroxidof sodium.

The preferred dyestufi' for use in this process is a direct or substantive dye. I have also used some of the vegetable dyes along with direct dyes, but not with as good results as with the direct or substantive dye alone.

The specific procedure for carrying out my process is as follows, although I do not desire to be limited to the exact detailsgiven.

The cloth is run into the dye machine,

amqunt of the alkaline oxidizing agent is added to the bath and the goods are allowed to run thirty minutes without steam. Steam is then turned on and the bath brought to a boil and continued there for fifteen minutes. Steam is again turned off and the goods allowed to run in the bath without steam for thirty minutes. The goods are then rinsed and the liquid extracted therefrom.

It has been found that sodium peroxid alone can be used satisfactorily as the alkaline oxidizing agent because when this material is subjected todecomposition in the bath, and upon the release of its oxygen, it generates sodium hydro oxid which is strongly alkaline, thus fulfilling the requirement that there should be a strongly alkaline oxidizing bath.

By the use of this modification of the process the patent above mentioned, practically any dyestuif may be used if it is permitted to first be attachedto the fiber of the goods and subsequently subjected to the action of the alkaline oxidizingagent as the dye when so attached to, the fiber is operatively unaffected by the alkaline oxidizing agent.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. The process of dyeing cotton. material containing motes, shives and, or, leaf which consists in subjecting the same to a dye bath and subsequently adding to said bath an alkaline -oxidizing agent for affecting said motes, shives and, or, leaf to remove the same.

2. The process of dyeing cotton material 4 containing motes, shives and, or, leaf which consists in first dyeing the goods in a bath and subsequently adding a substance to said bath which will remove the motes, shives and, or, leaf.

3. The process of dyeing cotton material containing motes, shives and, or, leaf which consists. in first subjecting the material to a bath containing a suitable dye until the material is given the desired shade, then subjecting the material to the action of a substance which will remove' the motes, shives and, or, leaf but will not adversely affect the dye or the said material.

4. The process of dyeing cotton containing specks which consists in subjecting the cotton to a dye until the desired shade is secured and then to an alkaline oxidizing agent to remove the specks.

5. The process of dyeing cotton material containing specks which consists inboiling saidv material in a bath containing a dye adding to the bath an alkaline oxidizing agent and again boiling said material. in said bath.

6. The process of dyeing cotton materia containing specks which consists in boiling said material in a bath containing a dye, adding a mordant and again boiling said bath and then adding an alkaline oxidizing agent and again boiling the material in said bath.

7 The process of dyeing cotton material which consists in boilingsaid material for about ten minutes in a bath containing a dye, adding a mordant to said bath and boiling it for about thirty minutes and then adding to sald bath an alkaline-oxidizing agent and again boiling the same for about fifteen minutes.

In testimony whereof, I have signed my name to this specification.

' HARRY B. SMITH. 

